Molding machine for foundry use



Dec, 2, 1924.I 1,517,798

. J. B. NEESHAM l MOLDING MACHINE FOR FOUNDRY USE Filed April 13, 923 2Sheets-Sheet l De', 2, 1924. 1,517,798 .J. B. NEESHAM Y HOLDING MACHINEFOR FOUNDRY USE Filed April 15, 1925 2 Sheets-Sheet 2 Patented Dec. 2,1924.

tangas UNITED STATES PATENT OFFICE.

JOHN BIRCH NEESI-IAM, OF GLASGOW, SCOTLAND, .ASSIGNOR TO JOHN MACDONALD3: SON LIMITED, OF GLASGOW, SCOTLAND.

MOLDING- MACHINE FOR FOUNDRY USE.

Application 'filed April 13, 1923. Serial No. 631,749.

To @ZZ whom t may concern:

Be it known that I, JOHN BIRCH NEE- sI-IAM, of 4 Kelvinside Gardens,Glasgow, Scotland, a subject of the King of Great 5 Britain, haveinvented a certain new and useful Improved Molding Machine for FoundryUse, ofvwhich the following is a specification.

This invention relates to foundry moldl0 ing machines.

In such machines having lifting rams operated by liquid pressure theupward movement of the lifting ram is generally too rapid and jerky todraw the pattern from the mould without damage, whereas it is desirablethat the pattern Ishall be withdrawn from its mould without shock orjar.

To this end it has been proposed that the inlet orificeof the pressurefluid should be above the bottomv of the ram and that a small by-passshould be provided from the orifice to a point below the ram, in orderthat the ram should start and stop slowly. In another construction wherethe inlet orilice was below the ram it was proposed to attach to thebottom of the ram a iin to pass into the orifice 'and partially choke itduring a very small portion of the stroke so that the ram should startand stop slowly.

:i0 I have found it undesirable that the lift should be in two stages,and prefer that the rate of lift should increase gradually from thestart to near the end of the stroke. I have also found that there is nonecessity for .5 a gradual check at the end of the exhaust stroke.Accordingly. I provide a foundry molding machine having a lifting ramoperated by liquid under pressure, in which the liquid is so admittedinto the cylinder 1&0 that the rate of upward travel of the lifting ramis caused to increase gradually from a minimum at or near the bottom ofits stroke up to a maximum at or near the top of the stroke. The desiredeffect may be obtained by tapering the lower end of the lifting ram andproviding in the side wall ofthe ram cylinder, adjacent to the top ofthe tapered portion when the ram is in lowermost position, a valvethrough which the operating liquid is forced into the cylinder, whereby,as the ram rises, the tapered portion gives a gradually increasingpassage at the valve for the liow of the liquid and so allows agradually increasing quantity of the liquid to enter the ram cylinder inunit time.

air admitted into the chamber.

A separate exhaust valve may be provided and arranged to open on thereturn stroke of the ram to exhaust the liquid rapidly from the ramcylinder and thereby expedite the speed of operation of the machine. Theoperating liquid may be contained in a chamber formed in the base of themachine and forced into the cylinder by compressed air or other pressurefluid, and the exhaust valve may be so arranged between the chamber andthe bottom of the ram cylinder that when the pressure fluid is admittedto the chamber to raise the ram, the valve is closed but opensautomatically, to return the liquid rapidly from the cylinder to thechamber, when the pressure in the chamber is relieved to lower the ram.

Oil is particularly suitable for use as the operating liquid.

These and other features of the invention will be disclosed as embodiedin one constructional form of the invention which is illustrated, by Wayof example, on the accompanying drawing, whereon Fig. l is a partsectional elevation of the molding machine embodying the features of theinvention.

Fig. 2 is an enlarged sectional view of the lower part of the liftingram cylinder and appertaining parts.

The molding machine comprises a base A, having an oil chamber B, and anouter cylinder `C which is secured to the base. A jarring ram Disslidably arranged in the outer cylinder, between the inner wall of thelatter and a hollow intermediate stepped or shouldered sleeve E, and alifting ram F is slidably arranged within the sleeve which constitutesthe mould lifting ram cylinder. The jarring ram is operated by pressurefluid admitted to the cylinder C below the same while the lifting` ram,as hereinafter more fully explained, is operated by means of the oilcontained in the chamber B which oil is forced into the sleeve bycompressed The upper part of the jarring rain D is bifurcated and formstwo arms supporting the machine table G, while a cross head I-I attachedto the lifting ram is arranged between said arms and supports liftingbrackets J.

The bottom part of the intermediate shouldered sleeve E rests on a plate1 accommodated in a recess at the upper part of the oil chamber Bandprovided with an aper- As previously stated, the speed of the lifting ran1 gradually increases as the ram rises, thus ensuring that the mould islifted from the pattern gradually, without shock or jar. The rate ofupward movement of the lifting ram may be varied by adjusting thedistance of the inner end of the oil inlet valve K from the adjacentouter wall of the lifting ram.

rlhe oil for operating the lifting ram is used over and over again andthe supply in the chamber B only requires to be occasionallyreplenished.

Having now fully described my invention what T claim and desire tosecure by Letters Patent is l. A foundry molding machine having incombination, a mould lifting ram arranged for operation by liquid underpressure and means on the ram for gradually increasing the `ate ofupward travel of said ram to a maximum near the end of its stroke.

2. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for upward sliding movement by liquid underpressure admitted to said cylinder, and means on the ram so disposedrel'- atively to a liquid inlet in the cylinder wall that the rate ofupward travel of said ram is gradually increased to a maximum near theend of its stroke.

3. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, means for gradually increasing the rate of upward travel ofthe ram to a maximum near the end of its stroke, and means in thecylinder wall for assisting in regulating the possible supply of theoperating liquid to said cylinder.

il. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, means for gradually increasing the rate of upward travel ofthe ram to a maximum near the end of its stroke, and a valve adjustablyarranged in the cylinder wall for assisting in regulating the possiblesupply of the operating liquid to said cylinder.

5. A foundry molding machine having in conibn ation. a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, a tapered portion on the ram and a liquid inlet to thecylinder so disposed relatively to said tapered portion that the flow ofliquid is varied to gradually increase the rate of upward travel of theram to a maximum near the end of its stroke.

6. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, a tapered portion on the ram and a liquid inlet to thecylinder so disposed relatively lo said tapered poi tion that the flowof liquid is varied to gradually increase the rate of upward travel ofthe ram to a maximum near the end of its stroke, and means for rapidlyexhausting said liquid from the cylinder after the mould liftingoperation is completed.

7. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, means to vary the fiow of liquid to gradually increase therate of upward travel of the ram to a maximum at or near the end of itsstroke, means for regulating the supply of operating liquid to thecylinder', and a valve in the cylinder for rapidly exhausting saidliquid from the cylinder after the mould lifting operation is completed.

8. A foundry molding machine having a 1 cylinder, ay mould lifting ramarranged for operation within the cylinder by liquid under pressure,means to vary the flow of liquid to gradually increase the rate ofupward travel of the ram to a maximum at or near the end of its stroke,and a liquid exhaust valve in the cylinder comprising in combination, acasing and a plunger arranged for movement within said casing in onedirection by pressure fluid and in the other by resilient means.

9. A foundry molding machine having in combination, a hollow base, acylinder supported by said base, a mould lifting ram arranged foroperation within said cylinder by liquid under pressure, a-taperedportion on the ram and a liquid inlet in the wall of the cylinderadjacent to the top of said tapered portion when the ram is in lowermostposition, whereby the rate of upward travel of the ram is graduallyincreased to a maximum near the end of its stroke, a valve for assistingin regulating the supply of the operating liquid to the cylinder and ancxhaust valve projecting into the hollow base and arranged for operationby pressure Huid admitted to the hollow base.

10. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, means to vary the flow of liquid for gradually increasing therate of upward travel of the ram to a maximum near the end of itsstroke, a supply valve in the cylinder wall, meansl for adjusting theposition of the valve relatively to the side of the ram whereby thespace between the valve and the said side is varied to regulate thepossible supply of liquid to the chamber.

11. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, means to vary the flow of liquid for gradually increasing therate of upwardtravel of said ram to a maximum at or near the end of itsstroke, and an .exhaust valve comprisin a recessed plunger, a spring tomove the punger in one direction, :a .casing surrounding the plunger'and having small orifices to admit the pressure fluid behind the plungerto move it against 'the spring and large orifices adapted when thepressure fluid is not acting to coincide with ysimilar orifices'leadingthrough the 'plunger wall tothe recess therein for the exhaust liquid.

12. A foundry molding machine having in combinati-on, a cylinder, amould lifting ram arranged forl operation Within the cylinder by liquidunder pressure, a tapered portion on the ram and a liquid inlet in thewall of the cylinder adjacent to the top of the tapered portion When theram is in lowermost position, whereby the rate of upward travel of theram is gradually increased to a maXimum near the end of its stroke, and`an eX- haust valve comprising a recessed plunger, a spring to move theplunger in one'direction, a easing surrounding the plunger and havingsmall orifices to admit the pressure fluid behind the plunger to move itagainst the spring land large orifices adapted when the pressure fluidis not acting to coincide with similar orifices leading through theplunger Wall to the recess therein for the exhaust liquid.

13. A foundry molding machine having in combination, a cylinder, a mouldlifting ram arranged for operation within the cylinder by liquid underpressure, a tapered portion on the rain, a liquid inlet in the wall ofthe cylinder adjacent to the fop of the said ta` pered portion when theram is in lowernlost position, whereby the rate of upward travel of theram is gradually increased to a maximum near the end of its stroke, andan ex haust valve; the said inlet comprising a supply valve in thecylinder wall having means for adjusting the position of the valverelatively to the side of the ram whereby the space between the valveand the said side is varied to regulate the possible supply of liquid tothe ram chamber, and the said exhaust valve comprising a recessedplunger, a spring to move the plunger in one direction, a casingsurrounding the plunger and having small orifices to admit the pressurefluid behind the plunger to move it against the spring and largeorifices adapted when the pressure fluid is not acting to coincide withsimilar orifices leading through the plunger wall to the recess thereinfor the exhaust liquid.

14. A foundry molding machine including a fluid pressure operated mouldlifting ram, and means whereby the ram will directly control and cause agradual increase of the flow of fluid thereto for causing the upwardtravelof the ram to gradually increase to a maximum near the end of itsstroke.

In testimony whereof I aflix my signature in presence of two witnesses.

' JOHN BIRCH NEESHAM. Witnesses MARY GREEN, AGNES TILMovnn.

